In a mixing bowl, cream butter and sugar. Add egg and vanilla; mix well/.,Combine flour and baking powder; gradually add to creamed mixture.,On a lightly floured surface, roll dough into a 14 x 10-in rectangle.,Spread jam to within 1/2 inches of edges. Sprinkle nuts over the jam.,Roll up jelly-roll style, starting with a side.,Wrap in plastic wrap; refrigerate for at least 3 hours or overnight.,Unwrap and cut into 1/4-in. slices. Place 1 inches apart on greased baking sheets.,Bake at 375°F for 10 to 12 minutes or until lightly browned.,______